Opened 5 years ago
Last modified 14 months ago
#12957 new enhancement
Categories for finite (enumerated) sets
Reported by: | nthiery | Owned by: | nthiery |
---|---|---|---|
Priority: | major | Milestone: | sage-7.4 |
Component: | categories | Keywords: | |
Cc: | sage-combinat, SimonKing, novoselt | Merged in: | |
Authors: | Reviewers: | ||
Report Upstream: | N/A | Work issues: | |
Branch: | Commit: | ||
Dependencies: | #12913 | Stopgaps: |
Description (last modified by )
There still remains a lot of finite (enumerated) sets that are not in the appropriate categories::
sage: CartesianProduct([1,2],[2,3]).category() Category of enumerated sets sage: Set([1,2,3]).category() Category of sets sage: (GF(3) ^ 2) in FiniteEnumeratedSets() False sage: MatrixSpace(GF(3),2) in FiniteEnumeratedSets() False sage: LatticePolytope(matrix(ZZ, [[1,1],[0,1]])).category() Category of objects
See also: #12913
The following examples were originally in the ticket description but are good on sage-6.9.beta1
sage: Permutations().category() Category of infinite enumerated sets sage: DirichletGroup(5).category() Category of finitely generated finite commutative groups
Moreover, with Sage 7.4.beta0 we now have:
sage: CartesianProduct([1,2],[2,3]).category() ... DeprecationWarning: CartesianProduct is deprecated. Use cartesian_product instead See http://trac.sagemath.org/18411 for details. #!/usr/bin/env python Category of Cartesian products of finite enumerated sets sage: cartesian_product([[1,2],[2,3]]).category() Category of Cartesian products of finite enumerated sets sage: Set([1,2,3]).category() Category of finite sets
Change History (6)
comment:1 Changed 4 years ago by
- Milestone changed from sage-5.11 to sage-5.12
comment:2 Changed 4 years ago by
- Milestone changed from sage-6.1 to sage-6.2
comment:3 Changed 3 years ago by
- Milestone changed from sage-6.2 to sage-6.3
comment:4 Changed 3 years ago by
- Milestone changed from sage-6.3 to sage-6.4
comment:5 Changed 2 years ago by
- Description modified (diff)
comment:6 Changed 14 months ago by
- Cc novoselt added
- Description modified (diff)
- Milestone changed from sage-6.4 to sage-7.4
I have updated the description with the status as of version 7.4.beta0.
Regarding LatticePolytope
(one of the examples in the description), I would be reluctant to consider it a finite enumerated set. There should be a distinction between the lattice polytope (an infinite set) and the set of its lattice points. The latter (which also makes sense for non-lattice polytopes) should be made a finite enumerated set.
On sage-6.9.beta1 things get better... I modified the description accordingly